Under 24 months are free. If child can sit on your lap, you should be fine.
Lori is correct, but there is a great A-Z guide to the ballpark and many questions on the Giants website under the AT&T PARK drop down at the top of the page. It is an excellent resource and one I used extensively when planning the trip to the April 4th kids home opener. It wasn't my first game, but was for my 10 year old daughter and there was much more planning involved than when I'm solo. It was an invaluable tool.
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